and joined by carla, the deputy director of spur and one of the persons who pushed this shelter in place and safe enough to stay concept and we want to talk about what it means and why it's important to san francisco. >> as you know the bay area as 63% chance of having a major earthquake and it's serious and going to impact a lot of people and particularly people in san francisco because we live on a major fault so what does this mean for us? part of what it means is that potentially 25% of san francisco's building stock will be uninhibit tabl and people can't stay in their homes after an earthquake. they may have to go to shelters or leave entirely and we don't want that to happen. >> we want a building stock to encourage them to stay in the homes and encourage them to stay and not relocate to other locations and shelters. >> that's right so that means the housing needs to be safe enough to stay and we have been focused in trying to define what that means and you as a former building official knows better than anybody the code says if an earthquake happens it won't kill you but doesn'